You are looking at
1
-
4
of
4
items for

A. JAGGANNADHA RAO, H. G. MADHWA RAJ and N. R. MOUDGAL

Summary.

Administration of lh antiserum to intact pregnant hamsters on any day from Days 6 to 11 of pregnancy resulted in termination of gestation. Following lh antiserum injection, the ovarian weights were markedly reduced.

A. JAGANNADHA RAO, H. G. MADHWA RAJ and N. R. MOUDGAL

Summary.

When monospecific and well-characterized antiserum to highly purified ovine lh was administered to pregnant hamsters before Day 4, implantation of the ovum was inhibited. Injection of the antiserum between Days 5 and 11 resulted in termination of pregnancy. These effects were accompanied by a reduction in ovarian weights and luteal degeneration. A combination of progesterone and oestradiol-17 β were required for complete reversal of the effects of antiserum on implantation and pregnancy. The antiserum was not effective in terminating pregnancy when administered after Day 11. Injection of antiserum to ovine fsh did not alter the course of gestation. Of the three gonadotrophins (fsh, lh and prolactin) administered, only the fsh—lh combination could postpone parturition. From these observations, it can be concluded that deprivation of lh essentially affects luteal function in the pregnant hamster.

H. G. MADHWA RAJ, M. R. SAIRAM and N. R. MOUDGAL

Summary.

The use of specific anti-fsh and anti-lh substances has shown that lh is the only pituitary gonadotrophin involved in the implantation process. Using different dosages of lh antiserum at different time intervals, it has been possible to arrive at a minimum effective dose (0·05 ml) which, when given on the 4th day at 10.00 hours, results in inhibition of implantation on the 8th day. We have shown that, at this dose, the antiserum is mainly inhibiting the oestrogen surge. It is proposed that an lh surge precedes an oestrogen surge on Day 4 of pregnancy.

Summary.

The relative rôles of FSH and LH in ovulation induction in immature and adult cycling rats and hamsters have been evaluated. Both heterologous purified pituitary hormones and homologous crude pituitary extracts have been used as ovulatory stimuli in immature animals primed with PMSG. Well-characterized FSH and LH antisera have been used in the above model systems to achieve specific neutralization of FSH and LH. The present study revealed that LH is the physiological trigger needed for induction of ovulation in both rats and hamsters and FSH cannot, by itself, induce ovulation in the total absence of LH.